The provisions of this article shall apply to contracts by
public entities as provided for in the Improvement Act of 1911
pursuant to Division 7 (commencing with Section 5000) of the Streets
and Highways Code.

Nothing in this chapter shall be deemed to relieve any city
or public agency, if the work or improvement is to be performed by
the city or public agency, from any competitive bidding requirements
imposed, as to work performed by the city or public agency, by any
charter or statutory provision applicable to it.